Bread samples were purchased from different supermarkets
with their own bakery and were packaged mainly in paperboard
bags (sometimes with a plastic window) or in plastic film. The
analysed samples presented variable contamination levels (MOSH
up to n-C35 ranged from 0.7 to 26.4 mg kg1) from different
sources, as confirmed by the LC–GC traces, characterised by the
presence of one or more humps comprising hydrocarbons of
different molecular weight, centred on n-C17–C19, n-C28, n-C30
and n-C33. Particularly, the most contaminated was a sample
whose LC–GC profile evidenced a POSH contamination up to
n-C25 (5.7 mg kg1) and a MOSH contamination in the range from
about n-C25 to about n-C45, centred on n-C33 (20.7 mg kg1 of
MOSH from n-C25 to C35) with no detectable MOAH. About half
of the samples contained detectable amounts of MOAH in the same
range of hump volatility centred around n-C18, as typical for
mineral oil migrating from packaging made with recycled fibres.
The most contaminated was a sample of milk bread with
2.2 mg kg1 MOAH in the range n-C10–C35.